Step 1: Butter the bread slices with 1/2 tablespoon (1 1/2 teaspoons) of the butter. Place one slice buttered side down on a work surface. Spread the top with about 1 1/2 tablespoons of the Russian dressing. Arrange the pastrami on top, followed by the cheese, sauerkraut, and dill pickle slices.

Step 2: Spread the second slice of bread with the remaining 1 1/2 tablespoons of Russian Dressing. Place the slice of bread, dressing side down and butter side up, on top of the pickles.

Step 3: If you are cooking the sandwich in a skillet: Melt the remaining butter in a large cast-iron or nonstick skillet over medium heat. Add the sandwich and place a grill press or second heavy skillet on top. Cook the sandwich until the bread is brown and crisp, the cheese is melted, and the pastrami is hot, 2 to 3 minutes per side, carefully turning the sandwich over with a spatula. Reduce the heat as needed to keep the bread from browning too much before the cheese has melted.

If you are cooking the sandwich in a contact grill: Preheat the grill. When the grill is hot, place the sandwich in it and cook the sandwich until the bread is brown and crisp, the cheese is melted, and the pastrami is hot, 4 to 6 minutes.

Step 4: Cut the sandwich in half and serve it at once.